Combustion chamber

ABSTRACT

Combustion apparatus comprising a chamber having a generally vertical cylindrical upper portion having a tangentially positioned inlet. The chamber has a generally funnel-shaped lower portion which receives liquid and solid products of combustion which are discharged from an outlet at the bottom thereof. A waste gas outlet is in the lower portion adjacent the bottom outlet. The flow of waste gas along the lower portion keeps the solid and liquid products in a molten or flowable condition, and this is enhanced by the shape and disposition of the lower portion.

United States Patent Fritz et a1.

[ June 10, 1975 COMBUSTION CHAMBER Inventors: Jack J. Fritz, Buffalo;Theodore W.

Lucas, Jr., Williamsville, both of N.Y.

Assignee: Andco Incorporated, Buffalo, N.Y.

Filed: Dec. 14, 1973 Appl. No.: 424,812

U.S. Cl. 23/277 C; 110/8 A; llO/28 F Int. Cl F23c 9/04; F23g 7/06 Fieldof Search 23/277 C, 277 R; 55/461;

1lO/8 A, 28 F References Cited UNITED STATES PATENTS 2/1952 Doss 55/461X 5/1954 Wagner 110/165 A 2,725,950 12/1955 Christiansen ..23/277CPrimary Examiner.lames H. Tayman, Jr. Attorney, Agent, or Firm-Christel& Bean 5 7 ABSTRACT Combustion apparatus comprising a chamber having agenerally vertical cylindrical upper portion having a tangentiallypositioned inlet. The chamber has a generally funnel-shaped lowerportion which receives liquid and solid products of combustion which aredischarged from an outlet at the bottom thereof. A waste gas outlet isin the lower portion adjacent the bottom outlet. The flow, of waste gasalong the lower portion keeps the solid and liquid products in a moltenor flowable condition, and this is enhanced by the shape and dispositionof the lower portion.

10 Claims, 2 Drawing Figures PRIMARY COMBUSTION CHAMBER COMBUSTIONCHAMBER BACKGROUND OF THE INVENTION This invention relates to slaggingpyrolysis solid waste disposal systems, and more particularly to a newand improved combustion chamber for such systems.

In slagging pyrolysis solid waste disposal systems, waste material ischarged into a primary combustion chamber wherein it is reduced to aslag which can be tapped from the chamber and to a gaseous product whichis withdrawn from the primary chamber and conveyed to a secondarychamber wherein it is caused to burn to a completely oxidized conditionso as to eliminate toxic and noxious gases and odors. A slag-likepreduct also is removed from the bottom of the secondary chamber.

A problem encountered with the combustion chambers of such systems,particularly the secondary chamber, is a tendency of the slag materialreceived at the chamber bottom to solidify or become non-flowing so asto block the chamber discharge outlet. This can impair the operation ofthe system, often requiring it to be shut down to remove theaccumulation, and obviously is undesirable.

SUMMARY OF THE INVENTION It is, therefore, a primary object of thisinvention to provide a new and improved combustion chamber apparatus forthe burning of gaseous material to a completely oxidized state.

It is a further object of this invention to provide such a combustionchamber apparatus which maintains the solid and liquid products ofcombustion received in the chamber in a molten or flowable state.

It is a further object of this invention to provide such a combustionchamber apparatus for use as a secondary combustion chamber in aslagging pyrolysis solid waste disposal system.

The present invention provides apparatus for effecting combustion ofcombustible material, especially gases, comprising a combustion chamberhaving an upper portion wherein combustion of the material occurs and alower portion for receiving liquid and solid products of the combustionfor discharge from the apparatus. Waste gas from the combustion flowingthrough the lower portion of the chamber is utilized according to thepresent invention to keep the liquid and solid products therein in amolten or flowing state to insure the complete removal thereof. This isaccomplished by providing anoutlet for removal of the solid and liquidproducts adjacent the bottom of the chamber lower portion and a wastegas outlet adjacent the bottom outlet. The effect of waste gas flow onthe liquid and solid products, including heating and a spiraling orwhirling flow, is enhanced by the shape and disposition of the chamberlower portion.

The foregoing and additional advantages and characterizing features ofthe present invention will become apparent upon a reading of the ensuingdetailed description together with the included drawing wherein:

BRIEF DESCRIPTION OF THE DRAWING FIGURES FIG. 1 is an elevational view,partly in section, with some parts broken away and others showndiagrammatically, ofa combustion chamber apparatus according to thepresent invention; and

FIG. 2 is a sectional view taken about on line 22 in FIG. 1.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Referring now to FIG.1, a primary combustion chamber is indicated diagrammatically at 10 andcan be of the typeshown in US. Pat. No. 3,568,612 issued Mar. 9, 1971.Briefly, combustion chamber 10 would have an opening at the top intowhich waste materials can be charged for movement downwardly through thechamber. A hearth is located at the bottom of the chamber to which airat an elevated temperature and pressure is supplied so that the airmoves upwardly in chamber 10. The air supplied to the hearth is at atemperature sufficient to cause combustion in chamber 10 not only forconsiderable burning of the waste material but also for melting ofmetal, glass and other solid materials so that they can move downwardlyto the hearth in the form of a molten slag which is tapped therefrom ina suitable manner and upon cooling can be crushed and disposed of in asimple manner. Other primary chambers can be used.

The combustion in chamber 10, however, is incomplete and results in acombustible producers gas and vapors which are tapped from chamber 10 bya conduit 12 which leads to a secondary combustion chamber 16constructed according to the present invention. Combustion chamber 16comprises an outer shell 18 of steel or other suitable metal and aninner lining 20 of refractory material provided in a conventionalmanner. In preferred form the lining 20 comprises a combination ofrefractory brick and insulation material. Shell 18 and lining 20 arefabricated or otherwise formed to provide a generally cylindrical upperportion 22 of the combustion chamber which is closed at the top 24thereof and which is disposed generally vertically in the position ofuse. Secondary chamber 16 is provided with inlet means 26 forintroducing the material to be burned near the top of chamber 16. Theouter shell 18 and inner refractory lining 20 can be fabricated in amanner providing inlet 26 which is cylinderical in shape as shown infurther detail in FIG. 2 and which is connected to conduit 12 leadingfrom primary combustion chamber 10.

A conduit 28'is connected to conduit 12 near the connection of thelatter to chamber inlet 26 and is supplied with air from a fan 30. Fan30 and conduit 28 supply any air which may be needed for completecombustion of the material conveyed in conduit 12. The supply of air canof course be controlled by controlling the operation of fan 30 and, inaddition, conduit 28 may be provided with a control valve (not shown)therein. Thus mixingof the air from conduit 28 and the material to beburned from conduit 12 is provided before the material enters secondarycombustion chamber 16.

The gaseous material supplied to chamber 16 through conduit 12 is veryhot, having a temperature which may be sufficient to cause combustionwhen the material is mized with air from conduit 28. In order to insureignition of the material, however, there is provided a burner or ignitermeans 32 in the path of the material after it is admixed with thesecondary air from conduit 28 as shown in FIG. 2. Burner 32 can be ofvarious suitable types well known to those skilled in the art and ispositioned within the end of conduit 12 where it connects to inlet 26.

The combustion chamber 16 according to the presit invention alsoincludes a lower portion designated i in FIG. 1 for receiving the liquidand solid products the combustion in chamber 16, such products comonlybeing referred to as slag. Lower portion 36 is in |mmunication withupper portion 22 and is defined by -ntinuing or extending wall portionsof the outer shell i and inner refractory lining 20. These portions arebricated or otherwise formed to define lower portion i in a generallyfunnel-like shape or a generally coni- .l shape. In other words, portion36 is hollow and has :onverging cross-section proceeding in a downstreamrection, i.e., in the path of the gas flow through and lay from theupper portion 22. Furthermore, portion i is disposed with thelongitudinal axis thereof extendg at an angle to the longitudinal axisof the cylindrical vper portion 22. As a result, portion 36 includes afirst ner wall surface region or portion 40 which as shown FIG. 1 isdisposed so as to be positioned in the path downward flow of gaseousmaterial through the wer portion of the chamber 16 which flow is indi-.ted by the line 42. Thus the downward flow of gas ll] tend to contactor be incident on wall portion 40. )rtion 36 of chamber 36 includesanother wall or surce portion 44 which with wall portion 40 defines thennel-shaped region. Expressed differently, a plane lssing throughsurface 40 is disposed at a relatively rger angle to the longitudinalaxis of the upper cylinical portion 22 as compared to the angle betweena ane passing through surface 44 and that axis. The apparatus accordingto the present invention furer comprises first outlet means adjacent thebottom 'the lower portion 36 for removing the liquid and lid products ofcombustion i.e., the slag material. The ltlet means includes an openinggenerally designated 3 which is in communication with a conduit 50, themnection between conduit 50 and the outer surface the chamber lowerportion 36 being facilitated by eans of a reducer member 52. As shown inFIG. 1, the wnwardly inclined wall surface portion 40 leads to )ening48, and conduit means 50 is disposed with the ngitudinal axis thereofgenerally parallel to but offset spaced from the longitudinal axis ofthe chamber )per portion 22. The apparatus of the present inventionfurther comises second outlet means designated 56 in FIG. 1 for movingwaste gas from the combustion. Outlet means passage 56 is locatedadjacent the outlet means 48, preferred form being positionedimmediately next to adjacent the outlet 48 as shown in FIG. 1. Theoutlet lssage 56 is defined by extending portions of the outer ell 18and refractory material 20. Outlet passage 56 'nnects to a conduit 60for delivering the waste gas to suitable location for use or for furtherprocessing. 1e outlet means including passage 56 and conduit 60 disposedso as to cause an abrupt change in direction the flow of the waste gas.In particular, the inner surce 62 of the refractory material definingoutlet pasge 56 meets surface 44 at a relatively sharp edge llChapproaches a right angle edge. In the position of e shown in FIG. 1,wherein the longitudinal axis of e cylindrical chamber 22 is disposedvertically, the 'mmon longitudinal axis of the outlet passage 56 and'nduit 60 is disposed at an angle upwardly inclined lative to thehorizontal, for example at about 45. The apparatus of the presentinvention operates in e following manner. The combustion within chamber10, such as the pyrolysis of solid muncipal refuse, is incomplete, and acombustible producers gas and vapors, etc. are produced therein. Thisgaseous material is withdrawn from chamber 10 by conduit 12 which leadsto the secondary combustion chamber 16 of the present invention. Theapparatus 16 is positioned in use preferably so that the upper chamberportion 22 thereof is disposed generally vertically. Conduit 12 connectsto inlet 26 near the top of the chamber 16 and in a tangential directionas shown in FIG. 2 whereby the gaseous material will swirl therein andtend to impringe against the refractory material 20 of the chamber.During the operation the apparatus, walls of the chamber are hot andpromote burning of the material. Air needed for the complete combustionof the material conveyed in conduit 12 is supplied from conduit 28, andthe movement of the material in and along the chamber 16 will furtherpromote the admixing of the material and the air. The material burns inchamber 16, moving downwardly therealong in a spiral or whirling paththrough the upper portion 22 and then into and through the lower portion36.

Solid and liquid products of the combustion, i.e., the slag material,are received in the lower portion 36, and the spiralling or whirlingflow of the extremely hot gas flowing in the direction indicated by thearrows 42 serves to maintain the slag material in a flowable or moltenstate in the lower region 36. In particular, the disposition of surface40 as shown in FIG. 1 is such that the slag-like material flows therealong and is intimately contacted by or wiped by the extremely hotwhirling gas which heats this material so as to maintain the molten orflowable state of the slag material thereby enhancing the flow alongsurface 40 downwardly through the outlet 48. Keeping the slag material,i.e., liquid and solid products of combustion, in a flowable or moltenstate in the lower portion of the apparatus 16 advantageously preventsaccumulation or solidification which would otherwise tend to block theoutlet 48. This, in turn, insures continued efficient operation of theapparatus and avoids the need to shut down the apparatus to removesolidified or non-flowing slag from the region of the discharge outlet.Waste gas products of the combustion leave the region of the lowerchamber portion 36 through outlet passage 56 which, according to thepresent invention, is located adjacent, preferably immediately next tothe slag discharge outlet 46. Thus, by having the extremely hot wastegas travel through or along the entire length of the lower chamberportion 36 which receives the slag or liquid and solid products ofcombustion, the hot gas is exposed to the slag material for the maximumamount of time possible. The shape of the lower chamber portion 36 whichis generally funnel-like or frustro-conical and disposed in a mannersuch that inner wall surface portion 40 is positioned in the downwardwhirling or spiraling flow of gas promotes an intimate and effectivecontacting of the slag material by the hot gas. The slag materialreceived in region 36 flows downwardly and along the downwardly inclinedinner wall surface portion 40 to the outlet 48, and the material iscontacted by the spiralling hot gas which keeps the material in aflowing condition. As shown in FIG. 1, preferably a major portion of theinner surface of the funnel-shaped portion 36 is positioned in or acrossthe downward flow of hot gas. In addition, the foregoing is enhanced bythe dispostion of outlet passage 56 and conduit 60 which cause an abruptchange in direction of the flow of the waste gas exiting therethrough.

The slag or mixture of liquid and solid products of combustion exitsfrom the apparatus through a conduit 50 to a suitable storage orcollection facility. The waste gas exits from the apparatus throughconduit 60 whereupon it could be supplied to a waste heat boiler for therecovery of heat from the gas.

In the apparatus of the present invention there is a need to heat theconical region 36 for effective slagging operation. Region 36 is heatedby radiation from combustion of the gaseous material in combustionchamber 16. In addition, the fact that the cross-sectional area ofregion 36 decreases in the direction of gas flow causes an increase inthe velocity of the gases therethrough which, in turn, enhances theirconvection and radiation characteristics. Furthermore, the upwardinclination of conduit 60 will cause any slag products resulting fromauxillary combustion in conduit 60 to flow back downwardly to outlet 48.

The apparatus of the present invention thus adequately burns the gaseousproducts applied thereto and at the same time permits disposal of thenoncombustible carry-over material in a molten or semimolten state whichis flowable and does not interfer with operation of the apparatus. Thepyrolysis or solid municipal refuse drives off hydrocarbons whichprovides a valuable source of low-grade fuel which has present thereinlong-chain hydrocarbons liquids which are difficult to burn, sold carbonparticles, and noncombustible solids entrained in the gas flow. Thecombustion chamber 16 of the present invention adequately burns thisfuel and provides maximum heat recovery, minimum emissions of particularmaterial, a minimum amount of unburned carbonecous gases, and a disposalof the slag-like material in a flowable state which does not interferewith the operation of the apparatus. The apparatus of the presentinvention effects combustion of gases, tars and suspended particulatematerial in an efficient and effective manner.

Therefore, it is apparent that the present invention accomplishes itsintended objects. While a single embodiment of the present invention hasbeen described in detail, this is for the purpose of illustration, notlimitation.

We claim:

1. Apparatus for effecting combustion of combustible material,especially gases, tars, and suspended particulate material comprising:

a. a combustion chamber having a generally cylindrical upper portionwherein combustion of said material occurs and a lower portion forreceiving liquid and solid products of the combustion;

b. means for introducing the material to be burned into said chamber forflow therealong during combustion;

c. first outlet means in said lower portion adjacent the bottom thereoffor removing the liquid and solid products of combustion, said firstoutlet means being offset from the longitudinal axis of said upperportion; and

d. second outlet means in said lower portion adjacent said first outletmeans for removing waste gas from the combustion, said second outletmeans being located to cause the waste gas to travel along the entirelength of said lower portion, whereby said waste gas supplies heat tomaintain said liquid and solid products in a flowable state in saidlower portion of said combustion chamber to facilitate removal of saidliquid and solid products through said first outlet means.

2. Apparatus according to claim 1, wherein said lower portion of saidcombustion chamber is generally funnel-shaped and disposed with thelongitudinal axis thereof extending at an angle to the longitudinal axisof said cylindrical upper portion.

3. Apparatus according to claim 1, wherein said second outlet meanscomprises conduit means disposed so as to cause an abrupt change indirection of the flow of said waste gas.

4. Apparatus according to claim 1, wherein said first outlet meansincludes conduit means disposed with the longitudinal axis thereofdisposed generally parallel to but offset from the longitudinal axis ofsaid cylindrical upper portion.

5. Apparatus according to claim 1, wherein said upper portion of saidchamber is disposed generally vertically thereby directing the flow ofgas downwardly and wherein said lower portion is disposed so that a wallportion thereof leads to said first outlet means and is positioned inthe path of downward flow of gas.

6. Apparatus according to claim 1, wherein said means for introducingmaterial to be burned comprises a tangential inlet for causing agenerally spiral or whirling flow along said upper and lower portions ofsaid chamber.

7. Apparatus according to claim 1, wherein said upper portion of saidchamber is disposed generally vertically so as to direct the flow of gasdownwardly and wherein said lower portion is hollow and of convergingcross-section in a direction from said upper portion to said firstoutlet means.

8. Apparatus according to claim 7, wherein the central axis of saidlower portion is inclined and said first outlet means includes conduitmeans disposed with the longitudinal axis thereof disposed generallyparallel to but offset from the central axis of said upper portion.

9. Apparatus according to claim 7, wherein said second outlet meanscomprises conduit means disposed with the longitudinal axis thereofinclined upwardly so as to cause an abrupt change in direction of theflow of said waste gas.

10. Apparatus according to claim 1, wherein said upper portion of saidchamber is disposed generally vertically and said means for introducingmaterial to be burned comprises a conduit entering near the upper end ofsaid chamber so as to cause material to flow downwardly in a generallyspiral path along said chamber, wherein said lower portion of saidchamber is generally funnel-shaped and disposed so that a major portionof the inner surface thereof is positioned across the downward flow ofgas, wherein said first outlet means is adjacent the bottom of saidinner surface portion, and wherein said second outlet means is spacedfrom said inner surface portion.

1. APPARATUS FOR EFFECTING COMBUSTION OF COMBUSTIBLE MATERIAL,ESPECIALLY GASES, TARS, AND SUSPENDED PARTICULATE MATERIAL COMPRISING:A. A COMBUSTION CHAMBER HAVING A GENERALLY CYLINDRICAL UPPER PORTIONWHEREIN COMBUSTION OF SAID MATERIAL OCCURS AND A LOWER PORTION FORRECEIVING LIQUID AND SOLID PRODUCTS OF THE COMBUSTION; B. MEANS FORINTRODUCING THE MATERIAL TO BE BURNED INTO SAID CHAMBER FOR FLOWTHEREALONG DURING COMBUSTION; C. FIRST OUTLET MEANS IN SAID LOWERPORTION ADJACENT THE BOTTOM THEREOF FOR REMOVING THE LIQUID AND SOLIDPRODUCTS OF COMBUSTION, SAID FIRST OUTLET MEANS BEING OFFSET FROM THELONGITUDINAL AXIS OF SAID UPPER PORTION; AND D. SECOND OUTLET MEANS INSAID LOWER PORTION ADJACENT SAID FIRST OUTLET MEANS FOR REMOVING WASTEGAS FROM THE COMBUSTION, SAID SECOND OUTLET MEANS BEING LOCATED TO CAUSETHE WASTE GAS TO TRAVEL ALONG THE ENTIRE LENGTH OF SAID LOWER PORTION,WHEREBY SAID WASTE GAS SUPPLIES HEAT TO MAINTAIN SAID LIQUID AND SOLIDPRODUCTS IN A FLOWABLE STATE IN SAID LOWER PORTION OF SAID COMBUSTIONCHAMBER TO FACILITATE REMOVAL OF SAID LIQUID AND SOLID PRODUCTS THROUGHSAID FIRST OUTLET MEANS.
 2. Apparatus according to claim 1, wherein saidlower portion of said combustion chamber is generally funnel-shaped anddisposed with the longitudinal axis thereof extending at an angle to thelongitudinal axis of said cylindrical upper portion.
 3. Apparatusaccording to claim 1, wherein said second outlet means comprises conduitmeans disposed so as to cause an abrupt change in direction of the flowof said waste gas.
 4. Apparatus according to claim 1, wherein said firstoutlet means includes conduit means disposed with the longitudinal axisthereof disposed generally parallel to but offset from the longitudinalaxis of said cylindrical upper portion.
 5. Apparatus according to claim1, wherein said upper portion of said chamber is disposed generallyvertically thereby directing the flow of gas downwardly and wherein saidlower portion is disposed so that a wall portion thereof leads to saidfirst outlet means and is positioned in the path of downward flow ofgas.
 6. Apparatus according to claim 1, wherein said means forintroducing material to be burned comprises a tangential inlet forcausing a generally spiral or whirling flow along said upper and lowerportions of said chamber.
 7. Apparatus according to claim 1, whereinsaid upper portion of said chamber is disposed generally vertically soas to direct the flow of gas downwardly and wherein said lower portionis hollow and of converging cross-section in a direction from said upperportion to said first outlet means.
 8. Apparatus according to claim 7,wherein the central axis of said lower portion is inclined and saidfirst outlet means includes conduit means disposed with the longitudinalaxis thereof disposed generally parallel to but offset from the centralaxis of said upper portion.
 9. Apparatus according to claim 7, whereinsaid secoNd outlet means comprises conduit means disposed with thelongitudinal axis thereof inclined upwardly so as to cause an abruptchange in direction of the flow of said waste gas.
 10. Apparatusaccording to claim 1, wherein said upper portion of said chamber isdisposed generally vertically and said means for introducing material tobe burned comprises a conduit entering near the upper end of saidchamber so as to cause material to flow downwardly in a generally spiralpath along said chamber, wherein said lower portion of said chamber isgenerally funnel-shaped and disposed so that a major portion of theinner surface thereof is positioned across the downward flow of gas,wherein said first outlet means is adjacent the bottom of said innersurface portion, and wherein said second outlet means is spaced fromsaid inner surface portion.